Struvite-K and Syngenite composition for use in building materials

ABSTRACT

A composition and process for the manufacture thereof for use in a hybrid building material comprising at least in part Syngenite (K 2 Ca(SO 4 ) 2 .H 2 O) and Struvite-K (KMgPO 4 ·6H 2 O). Specified constituents, including magnesium oxide (MgO), monopotassium phosphate (MKP) and stucco (calcium sulfate hemihydrate) are mixed in predetermined ratios and the reaction proceeds through multiple phases reactions which at times are proceeding simultaneously and in parallel and reaction may even compete with each other for reagents if the Struvite-K reaction is not buffered to slow down the reaction rate). A number of variable factors, such as water temperature, pH mixing times and rates, have been found to affect resultant reaction products. Preferred ratios of chemical constituents and manufacturing parameters, including predetermined and specified ratios of Struvite-K and Syngenite may be provided for specified purposes, optimized in respect of stoichiometry to reduce the combined heat of formation to non-destructive levels.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a divisional of Ser. No. 14/457,826, filed Aug. 12, 2014, nowU.S. Pat. No. 9,422,193, issued on Aug. 23, 2016, which was anon-provisional application relying for priority on U.S. ProvisionalApplication No. 61/865,029, filed Aug. 12, 2013; on U.S. ProvisionalApplication No. 61/890,720, filed on Oct. 14, 2013 and on U.S.Provisional Application No. 61/892,581, filed Oct. 18, 2013, the entirespecifications of which are incorporated by reference as if fully setforth herein. Additionally, National Phase Application Ser. No.15/028,372, filed on Apr. 8, 2016, now pending, and relying for priorityon PCT Application No. PCT/US2014/060518, filed on Oct. 12, 2014, areboth related to the present application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to building materials and morespecifically to building materials in which a desired final compositionand ratio of Struvite-K and Syngenite is provided to impart specifiedand predetermined properties and characteristics to said buildingmaterials.

2. Background Art

For approximately four thousand years, and at least since Roman times,magnesium oxide (MgO) based cements have been used to build walls andstructures. Within the last 50 years, improved magnesium oxidecontaining materials have been used for batch manufacture of slurriesthat are then poured into panel molds where they are allowed to cure foran extended period of time. The resulting products impart rigidity andstructural integrity to said panel and thereby allow said panel to befastened to wall assemblies.

Wallboard typically has a density range of from about 1,600 pounds(lbs.) to about 1,800 lbs. per thousand square feet (lbs/MSF) (about 7.8kilograms (kg) to about 8.3 kg per square meters (m²)) of about one-halfinch (1.27 cm) board. Heavy or high-density gypsum wallboards are costlyand more difficult to manufacture, transport, store, and manuallyinstall at job sites. The recent trend has been toward lighter orlow-density boards. While wallboards having reduced densities throughadding lightweight fillers and foams are known, wallboard having adensity of less than about 1,600 lbs/MSF (about 7.8 kg per m²) in aone-half inch (1.27 cm) board, renders the resulting board of lowstrength and may make the board unacceptable for commercial orresidential use. Because extra high-density or heavy gypsum wallboardgenerally is not desirable for the reasons set forth above, research anddevelopment are proceeding apace in order to produce reduced weight ordensity boards without sacrificing board integrity and strength. Onemethod of reduction of board is to use novel or non-gypsum materials forthe core of the boards.

Struvite (NaH₄(PO₄).6(H₂O) has been known as a naturally occurringmineral for over a century, and has been the subject of study in thehealth process of animals and sewage treatment. See, for example, USPublished Patent Appl. No. 2013/0062289, among others. A more recentdevelopment has resulted in a similar, albeit artificially created,mineral, alternatively known as K-Struvite, Struvite-K or Struvite (K)(hereinafter “Struvite-K”), having the chemical formula(KMg(PO₄).6(H₂O)). This essentially man-made mineral has been thesubject of intense study because many of its salient characteristics,including its orthorhombic crystal structure, glassy sheen permittingsubstantially friction free motion, and resistance to heat transfer,have been found suitable in the building industry.

Because of these and other properties, and as a result of the desire inthe building and construction industries to find a feasible alternativeto gypsum boards as internal building materials, Struvite-K has beendetermined to provide a good heat resistant building board panel whileremaining slightly elastic and is comparable as to ease of manufactureon a mass scale as is gypsum board.

It is well known that such magnesium oxychloride containing panels aremore expensive, usually amounting to twice to three times the cost oftraditional gypsum building panel alternatives. Therefore, these typesof boards are not widely accepted as cost affordable building materialsfor wall boards or panels. Moreover, some of these magnesium oxychloridecontaining building panels produce free chlorine gas within the boardmaterial, and thus present major issues, such as leaching, foul odors,fastener and building structure corrosion. In addition, many of thesetypes of boards will breakdown and decompose over time as they are notchemically stable. These types of boards and panels are particularlysusceptible to long term water exposure, and are prone to fall apartunder long exposures to such conditions.

In recent years, environmental and health safety driven building codeshave mandated that only building materials capable of offering improvedwater resistance and or fire resistance can be used in certainconstruction structures and building methods. As a result, paperlessgypsum and traditional cement building panels have evolved to satisfythese requirements. However, gypsum is not and cannot ever be waterproof and or completely water resistant. Therefore, it is necessary thatwater resistant compounds, such as waxes or silicones, be added to theirformulation to impart acceptable water resistance. In doing so, fireresistance of these building materials may be compromised, as the waterresistant additives may contain chemicals that will contribute tofueling dangerous conditions during a fire.

Moreover, the traditional fiber cement and Portland cement buildingpanels are extremely difficult to handle and work with when used intraditional building practices, and thus require more time, labor andspecialized tools to prepare and install these types of building panel.

More recently, the international economic situation has affected thebuilding and construction markets. Consequently, construction companieshave been driven to seeking alternative building materials that offerimproved performance characteristics that are at least an order ofmagnitude greater than those of traditional gypsum and cement buildingmaterials while simultaneously matching the cost effectiveness thangypsum and cement building materials.

It is for solving the simultaneous cost and effectiveness divide, whileproviding for a continuous board line that the novel invention hereindisclosed has been developed. The twin considerations of functionaleffectiveness and reduction of costs, in the context of improved andengineered building materials designed to serve specific purposes, wouldprovide an ideal building material if all the considerations areadjusted to obtain such boards or panels. None of the heretoforedisclosed known prior art building board compositions can provide thesecapabilities None of the prior art methods known heretofore teach theinventive process of forming composite boards containing syntheticStruvite-K and Syngenite in specified ratios so as to provide desiredcharacteristics and features on wall board panels.

SUMMARY OF THE INVENTION

Accordingly, there is provided herein a new and improved composition andprocess for the production of a novel building material, comprising asstarting constituent compounds magnesium oxide (MgO), monopotassiumphosphate (MKP) and stucco (calcium sulfate hemihydrate). The reactionproducts, Syngenite (K₂Ca(SO₄)₂.H₂O) and Struvite-K (KMgPO₄.6H₂O)proceed through multi phase reactions, at times occurringsimultaneously. The reactions are basic in the case of the hemihydrateand water and acidic for the Magnesium Oxide/MKP, both reactions takingplace simultaneously and in parallel and may even compete with eachother if the Struvite-K reaction is not buffered (rate slowed down) toallow the hemihydrate enough time and water to fully rehydrate. It isconsidered that the Syngenite reaction needs to achieve its fulltemperature rise (typically an exothermic reaction will occur up to amaximum temperature of 140° F. (60° C.),—depending on the purity of thehemihydrate, as well as its concentration). In this case the firstco-reacting temperature rise as it is an endothermic reaction and theformation of Syngenite is taking place as a product of dissolution fromthe MKP-K is liberated from the MKP and together with the forminghemihydrate forms K₂Ca(SO₄)₂.H₂O(Syngenite) before the Struvite-K nearsits own initial temp rise (an exothermic reaction—temperatures can hit amaximum of 212 F.° (100° C.). This temperature rise, if left unchecked,may pose a major destructive effect to the hemihydrate portion of theformed Syngenite even after it becomes fully rehydrated. The inventiondisclosed and claimed herein is a preferred set of ratios of chemicalconstituents and a method of manufacture of gypsum boards on acontinuous line including predetermined and specified ratios ofStruvite-K and Syngenite for specified purposes, optimized in respect ofstoichiometry to reduce the combined heat of formation tonon-destructive levels.

In one embodiment, the core reaction is essentially:MgO+KH₂PO₄+2CaSO₄.1/2H₂O→KMgPO₄.6H₂O+K₂Ca(SO₄)₂.H₂O+Ca⁺²+2Mg⁺²+2(PO)₄)⁻³

In another embodiment, together with the initial constituents and traceadditives, the reaction may comprise several subreactions but theoverall general mechanism is as follows:3MgO+3KH₂PO₄+2CaSO₄.1/2H₂O+3H₂O→KMgPO₄.6H₂O+K₂Ca(SO₄)₂.H₂O+Ca⁺²+2Mg⁺²+2(PO₄)⁻³in the presence of Boric Acid (H₃BO₃), Naphthalene Sulfonate, SulfuricAcid (H₂SO₄) and a siloxane, such as polydimethylsiloxane or poly(methylhydrogen) siloxane. It should be noted that the reaction is not yetcomplete to achieve total reaction product mixtures, and the stuccohemihydrate (CaSO₄.1/2H₂O) will remain in excess, so that the remainingionic materials, i.e., (Ca⁺², 2 Mg⁺² and 2(PO₄)⁻³) will either reactwith the remaining stucco or will form salt agglomerations upon drying.The identification of the precise reactant products remaining in theamorphous state is pending. It is considered that at least some of thestucco hemihydrate and the Magnesium Oxide remain unreacted, and theseconstituents structurally remain in an amorphous, randomly distributedmatrix within the crystalline structures that are presented by thereacted Struvite-K and Syngenite, as shown in FIG. 1.

It should further be noted that the constituent materials may beprovided in varying predetermined ratios, and may be included inspecified ratios for the main constituents MgO:MKP as a 1:1 ratio up toa ratio of 1:3.0. Thus, although the constituent materials identifiedabove and the resultant reactant products are shown as having specifiedratios, it should be understood that varying the initial constituentratios, as has been done in trials described below, may change thereaction products and the amounts of reacted and unreacted constituents.Specified weight percent ranges are provided for in the followingproportions:

MgO: 3.33 to 70.00%

KH₂PO₄: 4.67 to 70.00%

CaSO₄.1/2H₂: 10.5 to 90.0% adding up to 100%.

In a more refined ratio of the constituent starting materials, thefollowing proportions are preferred:

MgO: 40.0 to 70.0%

KH₂PO₄: 10.0 to 40.00%

CaSO₄.1/2H₂O: 25.0 to 75.0% adding up to 100%.

To both of these solid constituent mixtures, water is added to commencethe reaction in the proportion in a range of from 100:20 up to 100:40solid to water. In a preferred form of the reaction, it is carried outin a reaction mixer in a continuous process, and the resulting slurrycomprising mostly Struvite-K, Syngenite and gypsum provides asemi-liquid paste that is used in association with or without a gypsumcore to provide one or more gypsum board products. In an optimalformulation, the ratio of MgO:MKP is from between 1:1.8 to 1:2.2, and ina most optimal formulation most closely most approximates 1:2.0.

In another embodiment, there is disclosed and claimed herein empiricallyderived ratios of constituent materials and guidelines for defining theprocess parameters in the manufacturing process of building materialscontaining unique building compositions including the mineralsStruvite-K and Syngenite. These preferred ratios define the reactantcomposition of magnesium oxide (MgO), a phosphate and a potassiumcontaining reactant, such as monopotassium phosphate (KH₂PO₄), andhemihydrate alpha and/or beta gypsum (CaSO₄. 1/2H₂O), in solution withwater (H₂O), together with judicious use of thermodynamic and kineticproperties of these chemical reactions, to guide the reactions in thedesired direction and thereby to obtain the unique building materialshaving the desired physical properties.

The mathematical ratios utilize thermodynamic and stoichiometricprinciples and are grounded in the laws of conservation of atomiccomposition, energy and mass. The mathematical ratios use a desiredcomposition in the final product building materials containingStruvite-K and Syngenite and are capable of predicting the followingparameters of the process to within an accuracy of 5% of the actualprocess conditions:

-   1. Thermodynamic quantities of the process, including but not    limited to the Gibb's free energy of formation, the enthalpy of    formation, and the entropy of formation;-   2. Rheology of the mixture, including but not limited to the density    and viscosity;-   3. Reactant masses and/or ratios of magnesium oxide (MgO),    monopotassium phosphate (KH₂PO₄), stucco, in the form of Hemihydrate    Alpha and or Beta gypsum (CaSO₄.1/2H₂O) and water (H₂O);-   4. pH conditions;-   5. Process conditions, including but not limited to temperatures and    pressures of reaction.

Using appropriate mathematical equations, a user may determine a greatvariety of possible formulas and process iterations toward providingunique building materials containing Struvite-K (KMg(PO₄).6(H₂O)) andSyngenite (K₂Ca(SO₄)₂.H₂O), all in accordance with the disclosure of thechemical reactions disclosed in aforementioned U.S. ProvisionalApplication Nos. 61/865,029 and 61/892,581. Use of the processes andinnovative methods described herein can provide cost efficient, ultralow weight wallboards having enhanced performance capabilities, such asmechanical strength, fire and moisture resistance and anti-microbialproperties.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be discussed in further detail below withreference to the accompanying figures in which:

FIG. 1 is photomicrograph of a void in the resulting material developedin one of the tested formulations to determine the local structure ofthe resultant reaction products;

FIG. 2 is a ternary graph showing the proportions of MgO:MKP:stucco forspecified trial runs and plots the various formulations used in thetesting regime; and

FIG. 3 is a schematic plan view showing in cross-section a plug flowmixer reactor such as may be utilized in the production of the inventivecompositions of matter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The precise quantitative equations are being refined with reliance onthe experimental data compiled to date. Certain qualitative trends canbe seen from preliminary lab results and scientific deductive reasoningusing known scientific principles. The above listed 5 process conditionsmay be used to predict the necessary starting conditions based on theyields of Struvite-K and Syngenite desired in the final mixture. Thepossible modifications of the initial parameters will now be describedin greater detail to show the effect of how varying any one particularparameter will change the ultimate resulting composition derived fromthe starting constituents.

To be avoided in the reaction is the overwhelming heat that theMagnesium Phosphate reaction generates (exothermically) which tends todestabilize/overwhelm the gypsum rehydration reaction and generateamorphous gypsum hemihydrate as an unwanted by-product. Thus, to providean appropriate buffer is considered essential. Boric acid is ideal toretard the Magnesium Phosphate reaction, while it also serves as amechanism to protect gypsum recrystallization against the adverseeffects of thermal shock when the Magnesium Phosphate begins to form.

Using sulphuric acid (H₂SO₄) to pretreat the water and furtheraccelerate the Struvite-K reaction may be helpful. To reduce costs ofmaterials, as much as 70% stucco of the overall formulation can be usedas a replacement beneficial co-reactant instead of Magnesium Oxide andmonopotassium phosphate (MKP), since the gypsum is significantly cheaperand lighter weight than these materials.

As a by-product and a point of unexpected discovery, Syngenite is alsogenerated, which is material that is more fire resistant than gypsum.However, Syngenite is not as strong and fire resistant as thecombination of Struvite-K and Syngenite. Syngenite also provides anincidental benefit as a compositing factor between the MagnesiumPhosphate and the gypsum hemihydrate, whereby it incorporatesplasto-elastomeric characteristics, thereby rendering the final productsignificantly less brittle as well as more flexible, increasingmanipulability, and making the board easier to score/cut. This is also asignificant improvement over known Magnesium “Oxychloride” boards, forexample, such as those described in U.S. Pat. Pub. 2013/0115835 andPortland cement based cement building panels.

Additionally, and ideally, silicone is added to the mix to achieve fourother complimentary characteristics,

-   1) forming a catalyzed silicone in the presence of the Magnesium    Phosphate and acids-   2) providing a mechanism for thermal resistance to the gypsum and    permits recrystallization of the Magnesium Phosphate-   3) serving to retard the Magnesium Phosphate reaction, and-   4) providing a defoaming material to break down any foam that may be    generated as a byproduct of the reaction of the Sulfuric Acid with    CaCO₃, which is a known impurity in natural gypsum. Increasing the    amount of silicone addition further imparts substantial water    resistance to the board, and in increase in catalyzed silicone even    more so. Total water resistance has been increased using    significantly a lesser amount of silicone than is typically    used/required to meet ASTM performance requirements for wet area    building panels. Testing has shown that a maximum absorption rate of    ≤2% may be achieved, while typically results on conventional water    resistant gypsum wallboard, glass-reinforced gypsum boards, produce    on average absorption that is at best 3.5% to 4% total water    resistance.

However, the materials generated as a result of the present inventionare by their nature water resistant and do not breakdown in the presenceof water as would for example, Magnesium Oxychloride boards ortraditional gypsum boards, which require the incorporation of waterresistant additives, such as wax or silicone. Incorporation of aPolysiloxane in the present formulations restrains water wicking intothe open areas and through the matrix of the products made in accordancewith the present invention, essentially making it water impervious to anextent that water is no longer able to wick into the material. Moreover,even when bulk water or vapor water either wicks into or is transferredinto the material/materials generated according to the presentinvention, it has no detrimental effect thereon and the materialmaintains its original strength. So as to prevent the intrusion of bulkor vapor water into and throughout the inventive compositions, aPolysiloxane is added only if complete water imperviousness is arequirement, for example, such as in regions and localities wherebuilding codes have driven the specification.

One method of using Struvite-K in building materials has been suggestedfor use in roads in replacement of Portland Cement. See for example:“Optimisation of the preparation of a phosphomagnesium cement based onstruvite and K-struvite” H. Hammi and A. Mnif, Laboratoire deValorisation des Materiaux Utiles, Centre National de Recherches enSciences des Matériaux, Technopole Borj Cedria, Soliman, Tunisie, MATECWeb of Conferences Vol. 3, page 01071 (2013). Such compounds are alsouseful in the production of other building materials, such as wallboardpanels, ceiling tiles, etc. Such uses require the efficient, timely andinexpensive production such that they can be incorporated into thestructural members in which they are being used.

It has been noted that the production of such compounds and theirability to set in a timely fashion is dependent on the stoichiometry ofthe various precursors to the final set product, which is essentially inthe form of KMg(PO₄).6(H₂O). That is, it has been found as a surprisingand unexpected result that the ratios of ingredients as follows willprovide the best results in the desired characteristics:

The following data is used to drive the rapidity and direction of thereactions:

-   1. Thermodynamic principles:-   a. Gibb's free energy of formation—the Gibb's free energy of    reaction will become more negative and, in part, more spontaneous as    higher Struvite-K yields are produced, as it is shown with the    faster reaction time when producing the samples.-   b. Enthalpy of formation—the enthalpy of formation will become more    negative as higher yields of Struvite-K are produced, as shown by    the larger temperature increase in such samples at constant masses.-   c. Entropy of formation—the entropy of formation will become more    negative as higher yields of Struvite-K are produced, due to    decreasing entropy during crystallization.-   2. Rheology of the reaction mixture:-   a. Density of the mixture—the density of the fluid before    crystallization will increase as higher Struvite-K yields are    produced, due to the increase bulk density of the mixture before    setting.-   b. Viscosity of the mixture—for the same reasons listed above, the    viscosity will increase as higher Struvite-K yields are produced.-   3. Reactant masses and stoichiometric considerations:-   a. Monopotassium phosphate (KH₂PO₄)—the monopotassium phosphate    requirement will increase as higher Struvite-K yields are produced    until the mass ratio of monopotassium phosphate (KH₂PO₄) to    magnesium oxide (MgO) reaches 3.37:1, from stoichiometric    considerations.-   b. Magnesium oxide (MgO)—the magnesium oxide requirement will    increase with higher Struvite-K yields until the mass ratio of    monopotassium phosphate to magnesium oxide reaches 3.37:1, from    stoichiometric considerations.-   c. Stucco (gypsum hemihydrate)—the stucco requirement will not be    affected by higher Struvite-K yields, as it is not considered in    this reaction.-   d. Water—the water requirement will increase as higher Struvite-K    yields are produced until the mass ratio of monopotassium phosphate    (KH₂PO₄) to water (H₂O) equals 2.96:1, from stoichiometric    considerations. Water temperature is also considered a factor.-   4. pH Requirements:-   a. Based on experimental data as the pH is lowered with the help of    any acid, the yield of Struvite-K increases, since the reaction    happens faster and it uses the raw materials at an increased rate.-   5. Process Reaction Conditions:-   a. The reaction, as theorized, is a thermodynamically driven    reaction. Therefore, starting at a higher temperature will yield    lower amounts of Struvite-K.

The chemical reaction providing the optimum results has been determinedto be:

the reaction occurring in the presence of small amounts of H₂SO₄, H₃BO₃,both acting as buffers for reducing the reaction rate, and one or moresiloxanes to restrain water wicking and Naphthalene Sulfonate as afluidizer.

The Struvite-K Reaction is an exothermic reaction and proceeds veryrapidly:MgO+KH₂PO₄+5H₂O→KMg(PO₄).6(H₂O).

The basic reactions that are considered to occur are set forth above andthe reaction process that is considered to occur is described below. Itshould also be understood that the precise reaction mechanism remainsunder study, and that certain reaction parameters, such as pH, watertemperature, and timing of mixing and additions, have been explored asseverely affecting the reaction rates, products and final structures.The information derived therefrom is expected to provide a base ofinformation that will enable customization of the reaction products andextent of completion of the reaction, as desired for specificapplications.

In the current invention, it has been found that the degree and lengthof mixing plays a significant role in both how the reaction proceeds andthe ultimate yield of Syngenite and Struvite-K. Using the ratios asprovided above, it has been found that minimal mixing yields higherratios of Syngenite and longer mixing yields higher ratios ofStruvite-K. Unexpectedly, it was discovered that a short mixing periodenables a first, low temperature generating exothermic reaction and,when the mixing is stopped minimally after 30 seconds to one minute,complete set/hardening of the slurry can take up to 50 minutes. X-RayDiffraction (XRD) tests have indicated that samples mixed this way yieldhigher amounts of Syngenite than Struvite-K, as well as elevated ratiosof unreacted MgO (Periclase has been observed) and Bassanite(CaSO₄.1/2H₂O). Though each sample appeared to be set after this shortmixing, in fact it was unexpectedly discovered that the sample had onlyformed a shell around an unset—still fluid—inner core, and that thesample was maintaining a temperature around 86° F. The shell was brokenopen and all materials were found to go back into solution immediatelywhen mixed with the still fluid inner core material. Further mixing foran additional 30 to 40 seconds instigated a second reaction—anexothermic reaction wherein the temperature climbed to a maximum of 212°F.—initially indicative of a magnesium phosphate reaction, but in fact,following an XRD test on this sample material, was determined tocomprise Struvite-K.

Subsequent prolonged multi and singular stage hand and high speed mixingof follow-up samples composed/formulated with an identical formulationas listed below, demonstrated dramatically elevated Struvite-K yieldratios.

XRD results demonstrate the benefit of prolonged mixing of the specificformulation and its ratios are set forth below:

TABLE 1 KMgPO₄•6H₂O K₂Ca(SO₄)₂•H₂O Unreacted MgO CaSO₄•0.67H₂O(Struvite-K) (Syngenite) (Periclase) (Bassanite) (PDF-00-035-(PDF-00-028- (PDF-00-045- (PDF-00-047- Samples 0812) 0739) 0946) 0964) A67.1 25.0 6.6 1.2 B 66.4 25.8 7.1 0.7 C 66.0 26.4 6.9 0.6 D 66.0 26.46.9 0.6

As a result of this discovery it is a product of the invention hereindisclosed that mixing as described above in combination with thespecific formulation shown above and raw material addition variationsdetailed below are novel and unexpected to one normally skilled in theart from the previously known magnesium oxide or magnesium oxychloridetype boards.

By varying the reaction stoichiometry above, the reactions can betailored to produce desired or customized percentages of the differentproducts. For example, the reaction can be customized to produce themaximum amount of Struvite-K, as above, or to produce a maximum of theSyngenite, or a suitable desired combination of the two.

Combining the formulation above with suitable changes to the followingranges imparts improved economic efficiencies relating to large scaleStruvite-K yield as a result of the process/formulation.

In order to generate more Struvite-K the following method is used:

-   a. Using a multi-stage mixing apparatus, such as a plug flow mixer    as shown in FIG. 3, multilevel pen and or scraper mixer or    combination of them, or using just a mixer that allows for a long    dwell time with raw material supply and feed-through/output controls    equivalent to a manufacturing speed for a typical 4 foot wide and ¼    to 1″ thick board ranging from approximately a minimum of 20    feet/min to a maximum of 750 feet/min. The raw materials that are    mixed and combined within the mixer are the following: (Dwell time    must be equal to or greater than and min of 4 minutes and a max of    12 minutes).    -   ≤17.2%=Magnesium Oxide (MgO): Lite dead burned, medium dead        burned, hard dead burned MgO, or a combination of any two or        three alternatives, are intended to optimize and reduce raw        material cost meanwhile yielding both efficient and optimal        performance features in the result composite generated slurry        formulation.    -   ≥34.5%=MKP (Mono-Potassium Phosphate or KDP Potassium Dihydrogen        Phosphate—KH₂PO₄) will improve the molar ratio of Magnesium        Oxide (MgO) to potassium Dihydrogen phosphate and also impart a        reduction in the rate of reaction via reduced rate of        dissociation. The preferred MKP or KDP may be either of a food        grade or agricultural grade.    -   ≤17.2%=Beta Hemihydrate (processed gypsum stucco—CaSO₄.1/2 H₂O):        as a co-reactant which generates an initial reaction that slows        the overall reaction via an initial rehydration/uptake of        associated water—an initial step which generates a first        temperature rise reaction, an endothermic reaction with the        potassium content (setting off a dissolution of the K from the        MKP to join with the forming dihydrate to form Syngenite). The        Hemihydrate may be of a minimum purity ranging from        approximately 65% to a maximum purity of 100%. The higher purity        hemihydrate improves the uptake of potassium as dihydrate is        forming and thereby further slows the secondary KMgPO₄.6H₂O        (Struvite-K) reaction and elevates the Struvite-K yield in the        final reaction. Because the exothermic reaction that generates        the KMgPO₄.6H₂O is so hot (up to 212° F. (100° C.)), the        rehydrated dihydrate portion of the derived Syngenite calcines        to a minor extent. The Potassium (K) that had been used up in        the first Syngenite reaction is then released into solution in        stages and is ultimately reused in the KMg₂PO₄.6H₂O generation        process.    -   31.1%=H₂O (Water)    -   Trace remaining additives all represent ≤1.5% of the overall mix        in total combined addition.    -   Sulfuric Acid (H₂SO₄): is added to the water to change the pH        and improve the instigation of the overall acid based reaction.    -   Boric Acid (H₃BO₃): Boric Acid is a significant additive        specifically because it offers a benefit to both endothermic and        exothermic reactions. In the first reaction it serves to protect        the hemihydrate to water rehydration from the heat of the        secondary MgO/MKP/H₂O reaction, and allows the forming Syngenite        to hold onto the K longer than if there were thermal shield        being provided by the Boric Acid. In the case of the MgO/MKP/H₂O        reaction the Boric Acid is known retarder to Magnesium Phosphate        Cement reactions.    -   Siloxanes, such as Polysiloxane (C₂H₆OSi)_(n),        polydimethylsiloxane (CH₃[Si(CH₃)₂O]_(n)Si(CH₃)₃), and others,        in very low addition amounts may be used as a defoamer as the        MgO/MKP and an impurity within the Hemihydrate source (CaCO₃)        reacts with the MgO in the presence of water to cause a foaming        reaction that is not desirable. If no impurities are present,        the Polysiloxane stays intact throughout the entire course of        the first and second reactions.    -   Naphthalene Sulfonate, such as C₁₀H₈NNaO₃S, in very low additive        amounts serves as a fluidizer or dispersant for the overall mix.-   b. Higher Purity Beta Hemihydrate: the higher the purity of the    hemihydrate the overall reaction slows down/retards and a greater    uptake of K in the initial reaction which in turn causes more    generation of Struvite-K in the final reaction as long as the    additives in their current disclosed addition ratios are    approximately maintained—but—there is a maximum yield limit that can    be obtained. Decrease of either the MgO or the MKP addition will    produce less Struvite-K. Increase in the MgO and or the MKP additive    should generate equivalent or greater yield ratios of Struvite-K,    but requires an increase in the Beta hemihydrate addition or an    increase in the hemihydrate purity. In this case the Boric and    Sulfuric Acid additions may also be increased.

The above described method changes the ratios somewhat so that combiningthe formulations that above with the following ranges will impartimproved economic efficiencies relating to large scale Syngenite yieldas a result of the process/formulation.

In order to generate more Syngenite, the following method is used:

-   a. The use of a multi-stage mixing apparatus such as a plug flow    mixer, multilevel pin and or scraper mixer or combination of both or    just a mixer that allows for a long dwell time with raw material    supply and feed-through/output controls equivalent to a    manufacturing speed ranging from approximately a minimum of 20    feet/min to a maximum of 750 feet/min. This permits the raw    materials being mixed and combined within said mixer to the    following ratios and will provide dwell times equal to or greater    than and min of 2 minute or a max of 12 minutes:    -   ≥17.2%=Magnesium Oxide (MgO): Lite dead burned, medium dead        burned, hard dead burned MgO, or a combination of any two or        three alternatives intended to best optimize raw material cost        while yielding both efficient and optimal performance features        in the result composite generated slurry formulation.    -   ≤34.5%=MKP (Mono-Potassium Phosphate or KDP Potassium Dihydrogen        Phosphate—KH₂PO₄) to improve the molar ratio of magnesium oxide        to potassium Dihydrogen phosphate and as well, impart a        reduction in the rate of reaction while via reduced rate of        dissociation.    -   ≥17.2%=Beta Hemihydrate (processed gypsum stucco—CaSO₄.1/2H₂O):        as a co-reactant which generates an initial reaction that slows        the overall reaction via an initial rehydration/uptake of        associated water—an initial step which generates a first        temperature rise reaction, an endothermic reaction with the        potassium content (setting off a dissolution of the K from the        MKP to join with the forming dihydrate to form Syngenite). The        Hemihydrate may be of a minimum purity ranging from        approximately 65% to a maximum purity of 100% wherein, said        higher purity hemihydrate improves the uptake of potassium as        dihydrate is forming and thereby further slows the secondary        KMgPO₄.6H₂O (Struvite-K) reaction and elevates the Syngenite        yield in the final reaction, if the exothermic reaction that        generates the KMgPO₄.6H₂O is not hot enough or in a range no        greater than 140° F. to 180° F. the rehydrating hemihydrate to        dihydrate and then Syngenite (requiring the presence of the        hemihydrate) does not calcine to any extent, and thus the        available K to yield Struvite-K is reduced and results in a        lower ratio of Struvite K to Syngenite.    -   31.1%=H₂O (Water)    -   The remaining additives all represent ≤1.5% of the overall mix        in total combined addition.    -   With the changes in the ratios between the MgO, MKP and the        CaSO₄.1/2H₂O to achieve desired results in the final product, as        described above, appropriate changes will be required in the        stoichiometry of these three ingredients.    -   Sulfuric Acid (H₂SO₄): is added to the water to change the pH        and improve the instigation of the overall acid based reaction.    -   Boric Acid (H₃BO₃): The Boric Acid is a desirable ingredient        specifically because it offers a benefit to both endothermic and        exothermic reactions. In the first reaction it serves to protect        the hemihydrate to water rehydration from the heat of the        secondary MgO/MKP/H₂O reaction, and allows the Syngenite as it        is forming to hold onto the K longer than if there were a shield        being provided by the Boric Acid. In the case of the MgO/MKP/H₂O        reaction, the Boric Acid is known to retard the Magnesium        Phosphate Cement reactions. The Boric acid contribution and        benefit to both reactions was not an intended result, and thus        was an unexpected discovery.    -   Siloxanes, such as Polysiloxane (C₂H₆OSi)_(n),        polydimethylsiloxane (CH₃[Si(CH₃)₂O]_(n)Si(CH₃)₃), and others,        in very low addition amounts are used as a defoamer as the MgO        and an impurity within the Hemihydrate source (CaCO₃) reacts        with the MgO in the presence of water to cause a foaming        reaction that is not desired at present. If no impurity is        present, the Polysiloxane stays intact throughout the entire        course of the first endothermic and second exothermic reactions.    -   Naphthalene Sulfonate, such as C₁₀H₈NNaO₃S, in very low additive        amounts serves as a fluidizer or dispersant for the overall mix.-   b. Higher Purity Beta Hemihydrate: the higher the purity of the    hemihydrate the overall reaction slows down/retards and a greater    uptake of K in the initial reaction which in turn causes more    generation of Syngenite in the final reaction as long as the    additives in their current disclosed addition ratios are    approximately maintained—but—there is a maximum yield that can be    obtained. Maintaining a second exothermic reaction that does not    exceed 180° F. (82.2° C.) is critical in generating a greater ratio    of Syngenite to Struvite-K. If you decrease either the MgO or the    MKP addition then you have less Struvite-K. In this case the Boric    and Sulfuric Acid additions must also be increased.-   2. To generate equivalencies of both Syngenite and Struvite-K—the    reactions must be balanced in a way to enable the second exothermic    reaction to exist within the 180° F. to 212° F. (82.2-100° C.)    range, but at a limited exothermic temperature and time of reaction    so as to reduce the ratio of Struvite-K formation.

It has been found that the mixture as set forth above provides asignificantly greater yield of the Struvite-K, up to 67%, thanheretofore provided by known processes, and all with a minimum ofadditional necessary inputs.

In the end, the gypsum component makes the board panel more affordableand the final product is a dramatic improvement both from a physical andlong-term performance standpoint over conventional gypsum panels. It isnaturally UV resistant, that is, protects against penetration ofultraviolet rays, so it needs no performance surface coating and it isextremely water resistant. A similar product described by Surace in GB2,445,660 (equivalent US Pat Pub. No. 2008/171,179) while being capableof being produced in a continuous and or batch process, clearly statesthat the use of hemihydrate gypsum stucco is to be avoided because ofthe requirement of significant energy input needed to dry thehemihydrate. In the above described, product because of the simultaneousproduction of Syngenite, a similarly stoichiometric reaction thatrequires no added external heat for drying, provides the necessarythermal energy for the reaction. This is a direct result of the reactionof the hemihydrate with the monopotassium phosphate (MKP).

In use, the boards having the specified compositions of Struvite-K inspecified ratios to the Syngenite can be tailored for specific desireduses.

An initial attempt to provide a light weight gypsum board was includedfollowing steps to obtain a sample result:

The initial base material formulation was a 1:1:1 mixture, that is,comprising in equal proportions MgO:MKP-(KH₂PO₄):stucco (hemihydrateCaSO₄.1/2H₂O), with the MgO, MKP and hemihydrate gypsum being added indoses of 15 g each as dry powder to the mixer and dry premixed for 45seconds to ensure homogeneity of the materials. Additional basematerials additions were 0.03 g silicone oil, comprisingpolymethylhydrogensiloxane, and a dispersant comprising 0.05 gpolynapthalene sulfonate.

To this base mixture following the dry mix for all samples below, 17 gwater (H₂O) was added. This base mixture was then used for several labruns, by the additions as noted in the table below, to obtain severalsamples as listed in TABLE 2. The mixture, including the water, wasmixed in a mixer (by hand) for a period of about 30 to 60 seconds in afirst phase, and then allowed to partially set and then mixing was againbegun on the product which had partially set in a shell around theoutside, leaving a central core still in a liquid state. When the mixingwas begun in the second phase, the set outer shell immediately went backin to solution, and after mixing again for about 30 to 45 seconds, thematerial was allowed to set completely.

TABLE 2 Sample Utilizing the above Base formulation the No. followingmaterials were added by weight 1 boric acid (H₃BO₃) 1 g 2 H₂SO₄ 0.05 g 3H₂SO₄ 0.05 g + boric acid (H₃BO₃) 0.25 g 4 H₂SO₄ 0.05 g + (H₃BO₃) boricacid 0.50 g 5 H₂SO₄ 0.05 g + boric acid (H₃BO₃) 0.25 g + an extra 2.25 gH₂O 6 H₂SO₄ 0.05 g + boric acid (H₃BO₃) 0.25 g + extra 7.5 g KH₂PO₄(1.5x of base form.) 7 H₂SO₄ 0.05 g + boric acid (H₃BO₃) 0.25 g + extra15 g KH₂PO₄ (2x of base form.) 8 Same as the base, except the ratio is1:2:1 of the MgO:MKP - (KH₂PO₄):stucco hemihydrate (CaSO₄•½H₂O)

For each of these samples, the resulting materials were analyzed forcontent, and homogeneity. Quantitatively, TABLE 3 below shows theresults, and these are similar in format to those of TABLE 1 above.

TABLE 3 KMgPO₄•6H₂O K₂Ca(SO₄)₂•H₂O Unreacted MgO CaSO₄•0.67H₂O Sample(Struvite-K) (Syngenite) (Periclase) (Bassanite) no. (wt. %) (wt. %)(wt. %) (wt. %) 1 23.1 46.6 29.1 1.2 2 20.0 49.2 29.9 1.0 3 18.7 48.831.5 1.0 4 19.4 47.4 32.2 1.0 5 23.0 47.4 28.6 .9 6 20.1 33.9 42.2 3.9 758.8 24.0 7.3 9.9 8 52.8 29.8 16.1 1.3

In addition to the above quantitative results, several observations weremade, including that the process yielded a formulation that was processfriendly and yielded a board with a stronger core. It was alsodetermined that changing the timing of the reactions by, for example,increasing mix time from one stage to two stages ranging from 45 to 90seconds yielded a stronger core material with water resistance withoutneed for wax or silicone. This is presumed to result form a higherStruvite-K yield. Finally, a close microscope examination of the setmaterials indicated that in many of the samples, crystallizationoccurred in a non-homogenous way in the final materials. That is, wellformed crystallization occurred. The crystals, believed to be Struvite-Kcrystals, were determined to have formed in a boundary layer around thevoid spaces and between the voids and rest of the mixed product. Aphotomicrograph of one of these is shown in FIG. 1. As can be seen, thephotomicrograph shows crystallization of the boundary between the voidspace and the surrounding matrix. This is understood to comprise acrystalline Syngenite/Struvite-K structure, resulting in betterstructural rigidity in the resultant composition.

In second batch of lab runs, a similar procedure was run as set forthabove. The following TABLE 4 shows the sample constituents again using abase mixture as follows:

15 g MgO, 15 g MKP (KH₂PO₄), 0.15 g H₂SO₄, 0.25 g boric acid (H₃BO₃),0.05 g dispersant. One difference in this base structure from the one inTABLE 2 above is that the amount of stucco (hemihydrate CaSO₄.1/2H₂O)was varied, requiring an increase in water as well.

TABLE 4 Sample Utilizing the above Base formulation the No. followingmaterials were added by weight 1A 15 g stucco, 20 g water 2A 20 gstucco, 24 g water 3A 25 g stucco, 28 g water 4A 30 g stucco, 32 g water5A 35 g stucco, 36 g water 6A 40 g stucco, 40 g water 7A 50 g stucco, 48g water 8A 60 g stucco, 56 g water 9A 15 g stucco, 27 g water, an extra15 g MKP 10A  50 g stucco, 34 g water

For each of these samples, the resulting materials were analyzed forcontent, and homogeneity. Quantitatively, TABLE 5 below shows theresults, and these are similar in format to those of TABLES 1 and 3,above.

TABLE 5 Unreacted KMgPO₄•6H₂O K₂Ca(SO₄)₂•H₂O MgO CaSO₄•0.67H₂OCaSO₄•0.5H₂O * CaSO₄•2H₂O Sample (Struvite-K) (Syngenite) (Periclase)(Bassanite) (Bassanite) (Gypsum) no. (wt. %) (wt. %) (wt. %) (wt. %)(wt. %) (wt. %)  1A 20.6 46.0 29.8 3.7 <0.1 <0.1  2A 14.0 45.1 27.6 <0.113.3 <0.1  3A x 56.6 26.9 <0.1 16.5 <0.1  4A x 57.4 21.5 <0.1 21.2 <0.1 5A x 50.7 21.5 <0.1 27.8 <0.1  6A x 44.0 21.4 <0.1 34.6 <0.1  7A x 43.414.9 <0.1 41.7 <0.1  8A <0.1 45.5 11.0 <0.1 43.5 <0.1  9A 66.2 27.0 6.8x <0.1 <0.1 10A <0.1 2.5 <0.1 3.2 <0.1 94.4 * An analytical incongruityis apparent in two distinct forms of Bassanite: CaSO₄•0.67H₂O (47-964)and CaSO₄•0.5H₂O (Bassanite). These phases are similar and are bothmodelled as Bassanite.

Additional samples, deviating from the 1:1:1 ratio of the previousmixtures and not using the base composition of the first eight samples,were made up by use of the following formulations listed individually inTABLE 6 below:

TABLE 6 Sample MgO/MKP No. Constituent materials Ratio 11A 15 g MgO,50.65 g mKP, 33.52 g water   1:3.38 (stoichiometric struvite production)12A 15 g MgO, 7.5 mKP, 20 g stucco, 24 g water, + 2.0:1.0 0.15 g H₂SO₄ +0.25 g boric acid (H₃BO₃) + 0.05 g dispersant 13A 15 g MgO, 7.5 mKP, 30g stucco, 32 g water, + 2.0:1.0 0.15 g H₂SO₄ + 0.25 g boric acid(H₃BO₃) + 0.05 g dispersant 14A 15 g MgO, 7.5 mKP, 40 g stucco, 40 gwater, + 2.0:1.0 0.15 g H₂SO₄ + 0.25 g boric acid (H₃BO₃) + 0.05 gdispersant 15A 15 g MgO, 7.5 mKP, 50 g stucco, 48 g water, + 2.0:1.00.15 g H₂SO₄ + 0.25 g boric acid (H₃BO₃) + 0.05 g dispersant

For each of these samples, the resulting materials were analyzed forcontent, and homogeneity. Quantitatively, TABLE 7 below shows theresults, and these are similar in format to those of TABLES 1, 3, and 5above.

TABLE 7 Unreacted KMgPO₄•6H₂O K₂Ca(SO₄)₂•H₂O MgO CaSO₄•0.67H₂OCaSO₄•0.5H₂O * CaSO₄•2H₂O Sample (Struvite-K) (Syngenite) (Periclase)(Bassanite) (Bassanite) (Gypsum) Mg(OH)₂ no. (wt. %) (wt. %) (wt. %)(wt. %) (wt. %) (wt. %) (Brucite) 11A No data available 12A <0.1 36.321.2 <0.1 19.9 <0.1 22.6 13A <0.1 33.2 10.8 <0.1 29.5 x 26.5 14A <0.127.0 4.3 <0.1 36.8 12.1 19.8 15A x 30.6 5.6 <0.1 <0.1 <0.1 25.9

As is evident in samples 12-15, a significant amount of the Magnesiumoxide (MgO) failed to take part in the main reaction and insteadgenerated a significant amount of a reaction by-product of a mineralidentified as Brucite, (Mg(OH)₂), which was not present in the othersamples.

A third lab test of 11 samples was conducted and a similar manufacturingprocedure was run as set forth above. This test run was specificallydirected to determine what variables in the production affect differentspecified characteristics of the resultant material compositions. Thecharacteristics tested for across the different sample formulations werewater absorption, shrinkage in a furnace muffle test that is a directindicator of fire reissuance, and mechanical strength. The formulationswere similar to those tested above, with the omission of the additives,such as boric acid, Polysiloxane, Lignosulfonate, Sulfuric acid, etc. Toisolate the variable tested for, only the four essential constituentswere utilized including the group magnesium oxide (MgO), Mono-PotassiumPhosphate-MKP (KH₂PO₄), stucco (CaSO₄.1/2H₂O). The samples had theformulations with the water comprising 30 weight % of the final mixture:

TABLE 8 Sample The formulations of the following solid materials Sameformulation including 30 weight ID only, by weight percent, and wateradded 30% percent of water A MgO 62.5, MKP (KH₂PO₄) 12.5, stucco 25.0,MgO 43.75, MKP (KH₂PO₄) 8.75, stucco 17.50, water water 30.0 B MgO57.67, MKP (KH₂PO₄) 28.33, stucco 15.0, MgO 39.67, MKP (KH₂PO₄) 19.83,stucco 10.5, water water 30.0 C MgO 50.0, MKP (KH₂PO₄) 25.0, stucco25.0, MgO 35.0, MKP (KH₂PO₄) 17.50, stucco 17.50, water water 30.0 D MgO43.33, MKP (KH₂PO₄) 21.67, stucco 35.0, MgO 30.33, MKP (KH₂PO₄) 15.17,stucco 24.50, water water 30.0 E MgO 42.50, MKP (KH₂PO₄) 42.50, stucco15.0, MgO 29.75, MKP (KH₂PO₄) 29.75, stucco 10.5, water water 30.0 F MgO37.5, MKP (KH₂PO₄) 37.5, stucco 25.0, MgO 26.25, MKP (KH₂PO₄) 26.25,stucco 17.50, water water 30.0 G MgO 32.5, MKP (KH₂PO₄) 32.5, stucco35.0, MgO 22.75, MKP (KH₂PO₄) 22.75, stucco 24.50, water water 30.0 HMgO 31.67, MKP (KH₂PO₄) 63.33, stucco 5.0, MgO 22.17, MKP (KH₂PO₄)44.33, stucco 3.50, water water 30.0 I MgO 28.33, MKP (KH₂PO₄) 56.67,stucco 15.0, MgO 19.83, MKP (KH₂PO₄) 39.67, stucco 10.5, water water30.0 J MgO 25.0, MKP (KH₂PO₄) 50.0, stucco 25.0, MgO 17.5, MKP (KH₂PO₄)35.0, stucco 17.5, water water 30.0 K MgO 21.67, MKP (KH₂PO₄) 43.33,stucco 35.0, MgO 15.17, MKP (KH₂PO₄) 30.33, stucco 24.5, water water30.0 L MgO 16.67, MKP (KH₂PO₄) 43.33, stucco 50.0, MgO 11.67, MKP(KH₂PO₄) 23.00, stucco 49.0, water water 30.0 M MgO 10.0 MKP (KH₂PO₄)33.33, stucco 70.0, MgO 7.0 MKP (KH₂PO₄) 14.33, stucco 70.0, water water30.0 N MgO 3.33, MKP (KH₂PO₄) 6.67, stucco 90.0, MgO 2.33, MKP (KH₂PO₄)4.67, stucco 63.0, water water 30.0 O MgO 12.5, MKP (KH₂PO₄) 62.5,stucco 25.0, MgO 8.75, MKP (KH₂PO₄) 43.75, stucco 17.5, water water 30.0

As a visual aid, the solid constituents, by weight percent have beenmapped in a ternary diagram as illustrated in FIG. 2. As can be seenfrom a comparison of the plots of the different formulations in thephase diagram, some like L, M and N are high stucco formulations, A-Dare high MgO formulations, and group comprising H-N are high MKPformulations, while E, F and G are equally weighted between MgO and MKP.As can be seen by the linear progression of the connecting lines in thevertical directions, a pattern was intended to maintain as constantratio between MgO and MKP while varying only the stucco content. In thehorizontally aligned points, the stucco content is maintained constantand the ratio between MgO and MKP is varied. As result of the testing inthe different formulations and trends seen from the compiled data, andthe following major indications are provided as described below.

It should also be appreciated that the weight percent of water in thesamples set forth above was nominally set at 30 weight percent, thepercentage of water relative to the solid constituents can also bevaried anywhere from 20 to 40 weight percent, with 30 weight percentbeing nominally used as a benchmark for having a sufficient amount ofliquid solvent to initiate the reaction of the constituents.

It is also important to recognize that water temperature is a criticalfactor in the process. Specifically, the temperature of the water as itis added to the solid constituents is an important consideration as itaffects the rate of reactivity of the constituents. An increase in thetemperature of the water decreases the mix reactivity rate, andsimultaneously increases the time that must pass for the slurry to set.Standard water temperature is about between 20.0° C. and 25° C. Thus, itis important to monitor and control the reaction rates to such ratesthat maintain the integrity of the resulting product, as too high atemperature, that is, over 50° C., can lead to cracking of the surfaceduring the hardening process as the slurry sets. The main learning fromthis study is the inverse relationship of reaction rate when compared toinitial water temperature.

From the testing regime, the following clear trends for characteristicshave been determined: The inventive magnesium phosphate(Struvite-K/Syngenite) compositions exhibited significantly improvedcompression strength, water absorption and fire resistance compared to asimple Gypsum composition. Moreover, it has been determined that theproduct characteristics are indeed tunable with variables in the processparameters and raw material ratios and properties thereof. For example,those samples processed with lower water content exhibited highercompressive strength, higher fire and water resistance. Samples withhigher shear rate/time exhibited higher compressive strength andmarginal decrease in fire and water resistance. Shear rate and time isthe vigor with which the mixture is mixed in a mixer, the amount of timethe mixing process proceeds and whether the mixing was done by hand ormechanically.

Samples processed at cooler temperatures exhibited higher compressivestrength and marginal decrease in fire and water resistance.

Samples with MgO calcined at higher temperature exhibited higherstrength, samples with coarser MgO exhibited lower strength, whichexhibits an opposite behavior to that of water absorption and fireshrinkage properties.

Additionally, it was noted that initial water temperatures were crucialin amount of and timing of delivery of the water.

Another sample production in an inline production run was attempted onan actual board forming line, in which the lab runs were scaled up byabout 100 times to determine if the process is feasible for use ingypsum board production utilizing the inventive material combinations.Essentially the same formulations were utilized, with the obviousexception that all the amounts were scaled up, and a much larger mixerand reactor vessel or chamber was required. The procedure also needed tobe modified in significant ways to enable the continuous, rather thanbatch, production of the inventive material compositions for use in aboard line running at almost normal speed of running or a round 40 feetper minute.

Certain additional equipment was required for this production run notneeded in the lab runs, including a tank reactor, a mixer, one or morepumps, a roller coater, perhaps two one for each of the two surfacelayers, and a core gypsum mixer and pump for providing a continuous flowof the core gypsum, that is, the lightweight core gypsum, that will makeup the central layer that will ultimately comprise the central or corelayer having little if any of the Struvite-K and Syngenite reactionproducts. Thus, the final desired product is to be a surface layercoated with the inventive material compositions “wrapped around” agypsum core.

The procedure to manufacture the surface layer coatings is essentiallythe same as those described above, except adjustments are required to bemade for the vastly increased scale of the constituent materials. Thefollowing step-by-step procedure is expected to produce the necessarycoating layer:

Pre-mix the solid mixture, comprising a 1:1:1 ratio, that is,MgO:MKP-(KH₂PO₄):stucco (hemihydrate CaSO₄.1/2H₂O) the pre-mix phase tolast form between 30 to 60 seconds. To ensure that enough of the mixtureis made, it is expected that about a 15 kg amount of each of the baseconstituents is made. A proportional amount of siloxane and a defoamer,and a dispersant, such as polynapthalene sulfonate, may be added to thismixture.

Add water in about the same proportion, or about 17 kg.

Mix the resulting slurry for between 30 to 60 seconds in the largecontinuous mixer. After 15 seconds of mixing, the mixture started tosolidify. It has been found that continued mixing will re-liquify themixture. This is Phase I mixing.

Upon finishing with this initial mixing time, a timing sequence wascommenced. Each minute after this initial Phase I mixing time, themixture was again mixed vigorously for 5 second periods separated by 55second intervals. This is the Phase II mixing.

The formulation used in the production run causes the product to set-upanywhere from 5-20 minutes after the water is added to the powders. Dueto the type of mixer used, however, the mixing occurred unevenly, noproduct was obtained out of the mixer/reactor in any appreciable amountsfro technical reasons. Further testing is needed to validate the scaleup and continuous production run model.

The invention herein has been described and illustrated with referenceto the embodiments of FIGS. 1-3, but it should be understood that thefeatures and operation of the invention as described are susceptible tomodification or alteration without departing significantly from thespirit of the invention. For example, the variations in startingmaterials of the various elements, or the specified reaction conditionsmay be altered to fit specific applications and desired yields. Also,additional variations may be introduced to provide differences in theresulting materials. For example, alternative additives to the startingconstituents may include, in combination and or permutations of thelisting herein, Boric acid, Polysiloxane defoamer, Lignosulfonate,Sulfuric acid, deionized water, tap water, and others as these becomeknown to affect the reactions.

In addition, the mixing process and speed may be varied to obtain moreoptimal desired results. Other variables that may be utilized tooptimize results are used natural instead of Synthetic stucco, the orderand timing of additions and ingredients may be varied, and with theintroduction of productions runs, mechanical mixing of the constituentsin for example, pipe reactors or tube of a given length containingstatic mixers therein may enable multi-stage mixing of the constituentto provide a constant flow for in line flow mixing and just in timedelivery to the gypsum board forming table. Other variables that mayhave an effect on resulting ratios and products may include varying thesate as well as the ratio of the raw constituent materials. These mayinclude varying the addition rate, temperatures of the constituents,timing of additions, particle size, mix time, and other factors that maybe determined as experience is gained with the reaction processes.

Accordingly, the specific embodiments illustrated and described hereinare for illustrative purposes only and the invention is not to beconsidered as being limited except by the following claims and theirequivalents.

What is claimed is:
 1. A building composition for use in a buildingproduct comprising Struvite-K (KMgPO₄·6H₂O), Syngenite (K₂Ca(SO₄)₂H₂O),and one or more of stucco hemihydrate (CaSO₄·1/2H₂O), gypsum(CaSO₄·2H₂O), and Magnesium Oxide (MgO), wherein the one or more ofstucco hemihydrate, gypsum, and Magnesium Oxide are randomly distributedin a matrix within the crystalline structures that are presented byStruvite-K and Syngenite.
 2. The building composition for use in abuilding product according to claim 1, wherein: Struvite-K is present inan amount of from 0.1 to 67.0 weight percent; Syngenite is present in anamount of from 2.5 to 60.0 weight percent; and one or more of stuccohemihydrate, and Magnesium Oxide making up the remaining composition. 3.The building composition for use in a building product according toclaim 2, wherein: Struvite-K is present in an amount of from 15.1 to37.0 weight percent; and Syngenite is present in an amount of from 12.5to 46.0 weight percent; and one or more of stucco hemihydrate, andMagnesium Oxide making up the remaining composition.
 4. A fire-resistanthybrid wallboard comprising a composition according to claim
 1. 5. Thefire-resistant hybrid wallboard according to claim 4, further comprisinga facing material including a randomly aligned inorganic fibrous matwith a coating comprising the composition.
 6. The fire-resistant hybridwallboard according to claim 4, wherein the composition includes:Struvite-K in an amount of from 0.1 to 67.0 weight percent; Syngenite inan amount of from 2.5 to 60.0 weight percent; and the one or more ofstucco hemihydrate (CaSO₄·1/2H₂O), gypsum (CaSO₄·2H₂O), and MagnesiumOxide (MgO) making up the remaining composition.
 7. The fire-resistanthybrid wallboard according to claim 6, further comprising a facingmaterial including a randomly aligned inorganic fibrous mat with acoating comprising the composition.
 8. A fibrous mat comprising randomlyaligned inorganic fiber strands and a coating comprising a compositionaccording to claim
 1. 9. The fibrous mat according to claim 8 whereinthe composition comprises stucco hemihydrate and Magnesium Oxide. 10.The fibrous mat according to claim 8 wherein the composition comprises:Struvite-K in an amount of from 0.1 to 67.0 weight percent; Syngenite inan amount of from 2.5 to 60.0 weight percent; and the one or more ofstucco hemihydrate, gypsum, and Magnesium Oxide making up the remainingcomposition.
 11. The building composition of claim 1, wherein thecomposition comprises stucco hemihydrate and magnesium oxide.
 12. Thebuilding composition of claim 1, wherein the one or more of stuccohemihydrate, gypsum, and magnesium oxide are amorphous.
 13. The buildingcomposition of claim 1, wherein: Struvite-K is present in an amount offrom 0.1 to 67.0 weight percent; Syngenite is present in an amount offrom 2.5 to 60.0 weight percent; and one or more of stucco hemihydrate,gypsum, and magnesium oxide making up the remaining product.
 14. Thebuilding composition of claim 1, wherein: Struvite-K is present in anamount of from 15.1 to 37.0 weight percent; and Syngenite is present inan amount of from 12.5 to 46.0 weight percent; and one or more of stuccohemihydrate, gypsum, and magnesium oxide making up the remainingproduct.
 15. The building composition of claim 1, further comprising apolysiloxane or a silicone.
 16. The building composition of claim 1,wherein the gypsum is present.
 17. The building composition of claim 16,further comprising a dispersant.